Filtros ativos: comparação de técnicas de controle

• Autor(a) principal: Santos, Lucas Allan Oliveira dos
• Data de Publicação: 2019
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/50444
• topic: Filtros Ativos Paralelos; Teoria pq; Correntes Senoidais de Fryze; Compensação de harmônicos

With the increased use of electronic devices, which in most cases work nonlinearly by distorting the mains currents and/or voltages, greater attention and concern has been required with regard to power quality and the problems caused by excess nonlinear equipments connected to the power grid. Among the various problems caused by nonlinear loads connected to the power grid, we can highlight the increased losses on rotary machines stators and rotors, causing harmful overheating to the machines, additional losses caused by increased electric current RMS value, distortion in power grid voltages, improper actuation of electrical system protection devices, etc. All of these problems are caused by the circulation of harmonic currents in the power grid, which arise due to distortions in the power grid currents caused by nonlinear loads. One solution to mitigate the problem of harmonic currents circulation in the grid is the use of parallel active power filters, which have the function of supplying these harmonic currents for nonlinear loads, preventing such currents from being supplied by the electric grid. The present work performs the implementation of a shunt active power filter with controller implemented in the dSPACE platform. The shunt active filter will be implemented for harmonic current compensation in a three wire system. The control techniques to be studied are based on the pq Theory and the Fryze Sine Currents. Through the practical implementation of a power active parallel filter with pq theory based control and Fryze sine currents based control it was possible to improve the power quality by mitigating the harmonic content of the power grid currents. This improvement could be proven by analyzing the harmonic distortion rate (THD) of currents without and with the filter. For the first load setting used in this work (load 1), the THD without filter operation was around 17 %. With the filter operating with Theory pq and Fryze Sine Currents, the THD of the currents was around 6 %. For the second load setting used in this work (load 2), the THD without filter operation was around 40 %. With the filter operating with Theory pq and Fryze Sine Currents, the THD of the currents was around 13 %.